Ran 100 fwy miles with no oil cap

No warning lights came up? I would fill the oil and try it.

 

If you didn't lose all the oil and you've since refilled it the only issue you have is a dirty engine compartment... Make sure you clean it. Show us pics of what it looks like. I've always wondered?

 

First......if there was any oil on the dipstick at all, when wiped off and then re-inserted (engine off of course), then you didn't really lose that much. Fill it and don't worry.

As for cleaning the engine, that can cause more problems than it solves if you aren't careful.

 

But.... where did the oil cap go?

 

How much? Below the lower mark?

No oil pressure light, a little showing on dipstick; you could be fine. As others said, top it up and see how it goes.

I’ve done the same thing btw, with a previous vehicle. No long term problem.

 

How bad was the mess in the engine compartment? I know someone who had a huge mess with his Toyota truck when he did this, but have never seen how bad the mess is with a Prius?

 

It was a Honda Accord. Not too much mess. My wife was driving it more than me, and started noticing smell, from the cabin air intake. Never did that again; from then on: put the oil cap in vicinity of hood latch, so it can't close properly, if you were to forget the cap there.

 

Every time I add oil or do an oil change I always worry if I remembered to put the cap on... Over-active minds can think up problems that don't exist.

 

The cap location doesn't help. Recently did the oil change on my 2007 Prius and the cap is way in the back. Then I was checking the oil on my Odyssey and realized that when you put away the hood strut you end up staring right at the oil cap - kinda hard to forget.

 

have you filled the oil? replaced the cat?